[PATCH] D153953: Revert "[AMDGPU] Mark mbcnt as convergent"

[Sameer Sahasrabuddhe via Phabricator via cfe-commits]

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This reverts commit 37114036aa57e53217a57afacd7f47b36114edfb <https://reviews.llvm.org/rG37114036aa57e53217a57afacd7f47b36114edfb>.

The output of mbcnt does not depend on other active lanes, and hence it is not
convergent. The original change was made as a possible fix for

https://github.com/ROCm-Developer-Tools/HIP/issues/3172

But changing mbcnt does not fix that issue.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D153953

Files:
  clang/test/CodeGenOpenCL/builtins-amdgcn.cl
  llvm/include/llvm/IR/IntrinsicsAMDGPU.td


Index: llvm/include/llvm/IR/IntrinsicsAMDGPU.td
===================================================================
--- llvm/include/llvm/IR/IntrinsicsAMDGPU.td
+++ llvm/include/llvm/IR/IntrinsicsAMDGPU.td
@@ -1833,12 +1833,12 @@
 def int_amdgcn_mbcnt_lo :
   ClangBuiltin<"__builtin_amdgcn_mbcnt_lo">,
   DefaultAttrsIntrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i32_ty],
-   [IntrNoMem, IntrConvergent]>;
+   [IntrNoMem]>;
 
 def int_amdgcn_mbcnt_hi :
   ClangBuiltin<"__builtin_amdgcn_mbcnt_hi">,
   DefaultAttrsIntrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i32_ty],
-            [IntrNoMem, IntrConvergent]>;
+            [IntrNoMem]>;
 
 // llvm.amdgcn.ds.swizzle src offset
 def int_amdgcn_ds_swizzle :
Index: clang/test/CodeGenOpenCL/builtins-amdgcn.cl
===================================================================
--- clang/test/CodeGenOpenCL/builtins-amdgcn.cl
+++ clang/test/CodeGenOpenCL/builtins-amdgcn.cl
@@ -690,14 +690,12 @@
 
 // CHECK-LABEL: @test_mbcnt_lo(
 // CHECK: call i32 @llvm.amdgcn.mbcnt.lo(i32 %src0, i32 %src1)
-// CHECK: declare i32 @llvm.amdgcn.mbcnt.lo(i32, i32) #[[$MBCNT_ATTRS:[0-9]+]]
 kernel void test_mbcnt_lo(global uint* out, uint src0, uint src1) {
   *out = __builtin_amdgcn_mbcnt_lo(src0, src1);
 }
 
 // CHECK-LABEL: @test_mbcnt_hi(
 // CHECK: call i32 @llvm.amdgcn.mbcnt.hi(i32 %src0, i32 %src1)
-// CHECK: declare i32 @llvm.amdgcn.mbcnt.hi(i32, i32) #[[$MBCNT_ATTRS]]
 kernel void test_mbcnt_hi(global uint* out, uint src0, uint src1) {
   *out = __builtin_amdgcn_mbcnt_hi(src0, src1);
 }
@@ -834,7 +832,6 @@
 // CHECK-DAG: [[$WS_RANGE]] = !{i16 1, i16 1025}
 // CHECK-DAG: attributes #[[$NOUNWIND_READONLY]] = { mustprogress nocallback nofree nosync nounwind willreturn memory(read) }
 // CHECK-DAG: attributes #[[$READ_EXEC_ATTRS]] = { convergent }
-// CHECK-DAG: attributes #[[$MBCNT_ATTRS]] = {{.* convergent .*}}
 // CHECK-DAG: ![[$EXEC]] = !{!"exec"}
 // CHECK-DAG: ![[$EXEC_LO]] = !{!"exec_lo"}
 // CHECK-DAG: ![[$EXEC_HI]] = !{!"exec_hi"}


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